As long as you don't read your writes and use transform for animations it won't cost you more than 0.5ms to 1ms per frame (could it be better? Sure. But developer productivity is important.)
I use react in my game platform bloxd.io - which I work full time on - and I couldn't be happier
Just took at look a bloxd. Pretty cool! I want to make my own io game. I think the browser game market is under served as far as quality games are concerned, and doesn’t seem saturated compared to all the other platforms.
Would you be able to give any advice on netcode/multiplayer solutions? I like working with low level rendering libraries (canvas, Kha/Haxe) but I am wondering if it is better to use an engine versus libraries, or even just rolling my own solution with web sockets?
no need to roll your own solution. If you want to ship a game, go high level :D
For web native rendering pixijs is good for 2d (and phaser is good also a good entry level). For 3d theres threejs/babylonjs.
There's also unity, which some browser games use but it has downsides on web (large build sizes for one)
None of the networking solutions will give you unreal engine netcode developer productivity (and that includes ones for unity). I use colyseus, it doesnt solve everything but will save you some work
Re saturation, it definitely depends on the genre, web is its own market. What type of game are you thinking of making?
I use react in my game platform bloxd.io - which I work full time on - and I couldn't be happier